#include <iostream>
using namespace std;
const int N = 20;
int arr[N];
int dfs(int deep) // deep表示深度
{
    int res = 1;
    for (int i = 1; i <= arr[deep - 1] / 2; i++)
    {
        arr[deep] = i;
        res += dfs(deep + 1);
    }
    return res;
}
int main()
{
    int n;
    cin >> n;
    arr[1] = n;
    cout << dfs(2) << endl;
    return 0;
}